# OC4VM - recoveryOS Image Maker

## Introduction
This is a utility to download the recovery image, recoveryOS, for macOS from Apple's servers and create a bootable 
virtual disk file that can be used to start an Internet installation of macOS. It also has a Go port of the OpenCorePkg
macrecovery tool.

## Pre-requisites

### qemu-img

You will need to have qemu-img utility, from QEMU, on the path.

* Linux - These can be installed from Linux repos, for example Debian based distros

    `sudo apt install -y qemu-utils`

* macOS - use [brew](https://brew.sh) package manager to install on macOS

    `brew install qemu`

* Windows - use [Chocolatey](https://chocolatey.org) or [Scoop](https://scoop.sh) to install on Windows

    `choco/scoop install qemu`
   
## Instructions
1. Unzip the archive maintaining the folder structure
2. Open a console/shell in the folder with the tool for your OS and architecture.
3. Run the tool: `recoveryOS`
4. The menu will be displayed and just select the macOS version you want using the number on the menu.
```
OC4VM recoveryOS Image Maker
============================
Version 1.0.0-59580e8
(c) David Parsons 2022-25

Create a recoveryOS virtual image
1. Catalina
2. Big Sur
3. Monterey
4. Ventura
5. Sonoma
6. Sequoia
7. Tahoe

0. Exit
```

After downloading the DMG fie you are then prompted to select the virtual formats you want created from the base image.

```
Convert the recoveryOS virtual image
1. VMware VMDK
2. QEMU QCOW2
3. Micorsoft VHDX
4. Raw image
5. All
0. Exit
```
The tool will download the BaseSystem.dmg for the macOS version you selected and convert it to a virtual disk format.

After the tool has finished there will be 3 or more files present in the folder. For example if downloading Sonoma and
selecting all virtual disk formats there will be:

* sonoma.dmg
* sonoma.chunklist
* sonoma.vmdk
* sonoma.qcow2
* sonoma.vhdx
* sonoma.raw

The .dmg and .chunklist files are the original files downloaded from Apple and can be removed if not needed.

Occasionally you may get this error:

`ERROR: "HTTP Error 403: " when connecting to http://osrecovery.apple.com/InstallationPayload/RecoveryImage`

Just re-run the command and it should work.


## Acknowledgements
This tool is based on great open source software. Thanks to the authors of those tools.

* macrecovery.py - https://github.com/acidanthera/OpenCorePkg
* qemu - https://www.qemu.org
* qemu-img for Windows - https://cloudbase.it/qemu-img-windows